In the following equations, determined which reactant is the limiting reactant and which reactant is in excess. The amount used are given below.

KO+HNO3-> KNO3+H2O 15.4 KOH and HNO3 react.

1 answer

To determine the limiting reactant, we need to compare the moles of each reactant used to the stoichiometric ratio given by the balanced equation.

The balanced equation is:
2 KOH + HNO3 -> KNO3 + H2O

From the equation, we can see that 2 moles of KOH react with 1 mole of HNO3 to produce 1 mole of KNO3 and 1 mole of H2O.

First, we need to convert the given amounts in grams to moles.

The molar mass of KOH is 56.11 g/mol (from periodic table)
Moles of KOH = 15.4 g / 56.11 g/mol = 0.275 moles

The molar mass of HNO3 is 63.01 g/mol (from periodic table)
Moles of HNO3 = 15.4 g / 63.01 g/mol = 0.244 moles

Now, we can compare the moles of each reactant to the stoichiometric ratio.

The stoichiometric ratio tells us that 2 moles of KOH react with 1 mole of HNO3.

The ratio of moles of KOH to HNO3 is:
0.275 moles KOH / 0.244 moles HNO3 ≈ 1.13

Since the ratio is greater than 1, it means that there is more KOH than HNO3. Therefore, KOH is in excess and HNO3 is the limiting reactant.